Temperature control for ice making machine defrosting gases



Se t. 24, 1957 M. s. CHAPMAN 2,807,150

TEMPERATURE common. FOR ICE MAKING MACHINE DEFROSTING GASES Filed April1, 1955 3 Sheets-Sheet 1 SUCT/ON L l/VE L IOU/D A MMO/V/A HOT GAS'L/NGYVFRU/V 8. MA PMA/V,

BY M 2 ATTORNEYS Sept. 24, 1957 M. s. CHAPMAN "TEMPERATURE CONTRQL FORICE MAKING MACHINE DEFROSTING GASES Filed A il 1, 1955 3 Sheets-Sheet 2INVENTOR ATTORNEYS M. S. CHAPMAN 3 Sheets-Sheet 3 III iiiiii 1.1.1.13...A

I N VENTOR ATTORNEYS Sept. 24, 1957 TEMPERATURE CONTROL FOR ICE MAKINGMACHINE DEFROSTING GASES Filed April 1, 1955 TEMPERATURE CONTROL FOR ICEMAKING MACHINE DEFROSTING GASES Merlin S. Chapman, Wheeling, W. Va.Application April 1, 1955, Serial No. 498,582 2 Claims. (Cl. 2-7

The present invention relates to ice making machines and is moreparticularly concerned with the means for freeing ice from the surfaceagainst which it is formed by a slight thawing of its adjacent surfaceonly.

In known ice making machines a liquid refrigerant is is employed whichis introduced into one or more chambers while water is positioned orsprayed against the opposite side of the wall forming said chamberswhich water then becomes frozen due to the absorption of the heat by therefrigerant which then' turns into a gas. This gas is withdrawn from thechamber, compressed and condensed back to the liquid form forreintroduction into said chambers for further freezing purposes. The gasleaving the compressor in such machines is relatively hot and in somemachines is introduced into said chambers for freeing the ice from thetubes upon which it is formed to assist in its removal between theintroduction of the liquid refrigerant for forming the ice. Examples ofsuch machines are shown in U. S. Patents Nos. 2,598,430; 2,590,499;2,595,588 and applicants co-pending application for patent Serial No.305,534, now Patent No. 2,739,457, granted March 27, 1955.

However, in such known machines the temperature of the hot gas is notcontrolled and, accordingly, efficient defrosting of the ice is noteffected, nor can the temperature of the defrosting gas be varied asrequired due to the variation in the temperature surrounding saidmachine.

It is, accordingly, the principal object of the present invention toinclude in ice making machines means for increasing the temperature ofthe hot refrigerant gas employed for defrosting purposes.

Further objects of the invention will be in part obvious and in partpointed out in the following description of the accompanying drawingswherein,

Fig. 1 is a side elevation of an example of an ice making machineincorporating the present invention.

Fig. 2 is a cross sectional view showing the refrigerant pipes from thebottom of an ice making chamber.

Fig. 3 is a cross sectional view of the refrigerant intro ducing meansfor the exemplary ice making machine of Fig. 1 during the defrostingcycle.

Fig. 4 is similar to Fig. 3 except the elements are shown during thefreezing cycle.

Fig. 5 is a vertical section through a superheater for carrying out thepresent invention.

Fig. 6 is a vertical section through a modified form of superheater;and,

Fig. 7 is a horizontal section taken Fig. 6.

Referring now more particularly to the accompanying drawings, whereinlike and corresponding parts are designated by similar referencecharacters, there is shown by way of example only, an ice making machineincorporating the present invention and which machine is more fullydescribed in applicants co-pending application Serial No. 305,534, nowPatent No. 2,739,457, in order that the operation of the presentinvention can be on line 77 of Patented Sept. 24, 1957 "ice .v

understood. Referring first to Fig. 1, there is shown a tank 1 forreceiving a liquid refrigerant such as ammonia or Freon from theconventional refrigerant compressor and condenser for storing thisrefrigerant which by way of example is indicated as being ammonia,although other known refrigerants .can equally as well be employed.

Below tank 1 there is positioned a hollow header 2 from which extend aplurality of tubes 3. A plurality of pipes 4 extend from the bottom ofeach of said tubes and they are all connected to a pipe 5 which passesback to said tank 1.

Pipe 6 is connected to the exhaust end of the refrigerant compressor forreceiving hot compressed refrigerant gas therefrom and conveys this hotgas in the present example into a superheater 12 which for example, isthe same as shown in Fig. 5 or Figs. 6 and 7 and a plurality of pipes 7each leading into a hollow plug 8 closing one end of a tube 3, while acorresponding plurality of pipes 9 connect said plug 8 to a pipe 10which in turn is connected by a pipe 11 connected to a superheater 12similar to those shown in Figs. 5 and 6. Using the superheater ofFig. 5as an example of one type of device which can be employed for thepresent purpose, this superheater consists of a cylinder 12 having adisc 13 extending across one end forming a partition. Said disc has alarge plurality of openings 14 formed therethrough from each of whichextends a tube 15 down to a second disc 16 having a like plurality ofopenings 17 and forming a partition at the opposite end of saidcylinder. A pair of inlet and outlet pipes 18 and 19 extend through saidcylinder between said discs. A cover 20 having pipe 11 connected theretocloses the lower end of cylinder 12 while a similar cover 21 closes theupper end. A pipe 22 is connected to said cover 21 and extends to pipe23 connected to said header 2. A by-pass pipe 24 connects pipe 22 to thebase of the outlet cylinder 25, and extends to header 2. Within saidoutlet cylinder is positioned a closure piston 26 while a spring 27 ispositioned within the outlet 28 of said tank. A pipe 29' extends fromthe lower side of said cylinder 25 to header 2.

In the operation of the present machine, liquid refrigerant is fed fromthe conventional refrigeration condenser to tank 1 while refrigerantgases are drawn into the compressor for being recondensed. This liquidrefrigerant passes from tank 1 through outlet 28 to pipe 29 throughheader 2 to each of the tubes 3 where water in tubes 3 to tank 1 andthence through the suction line therefrom, and the liquid refrigerantremaining is discharged, during the harvest cycle, through pipes 4 intopipe 5, Y-shaped outlet 5' and pipe 5" back to tank 1.

At the same time hot gas under pressure from the highpressure side ofthe refrigeration system is in pipes 6 and upon the opening of thecontrol valve to this pipe the hot gas therein and in superheater 12',passes into pipe 7, and plugs 8 where the ice thereon and around thelower ends only of the tubes 3, is initially and slightly meltedwhereupon this gas continues through pipe 9 and 10 to pipe 11 intosuperheater 12, where its temperature is raised to the extent desired.

The resultant superheated gas from superheater 12, during the harvestingcycle, passes through pipes 22, 24 into cylinder 25 where, because it isheld under a much higher pressure than that in tank 1, it pushes piston26 against spring 27 into tank outlet 28 whereupon this superheated gasunder high pressure, passes downwardly through pipe 29 into header 2 andtubes 3 forcing out the liquid refrigerant therein through pipes 4, 5,etc., as described in applicants co-pending application hereinbeforementioned. While the liquid refrigerant is being so expelled from tubes3, the valve for pipe is opened for the passage of the refrigerant. Whenthe hot gas has replaced the refrigerant in tubes 3, the ice on tubes 3has its adjacent surfaces thawed sufliciently to allow the tubes of iceto'slide downwardly from said tubes 3. After the ice sheaths have beenremoved from the tubes 3 and so harvested, the timer closes the valve inpipes 6. Shortly thereafter the pressure beyond that point in the deviceillustrated in Fig. 1 equalizes, whereupon the valve 26 opens spillingrefrigerant from the tank 1 into the tubes 3 and intermediate parts,thus beginning another freezing cycle. The freezing and the harvestingcycles can be alternated by controlling the valves for pipes 5 and 6.

Steam, generated by means not shown, may be introduced through the pipesY19 and 19' into cylinders 12 and 12. By this means the gas passingthrough the tubes 15 is heated to the desired temperature in a manherWell understood.

By controlling the temperature of the steam in cylinders 12 and 12, thetemperature of the hot gas can likewise be controlled so that a hotterthan normal gas can be used to decrease greatly the time of theharvesting cycle and also to compensate for the loss of heat escapingfrom the pipes conveying the gas. Furthermore, these ice making machinesare generally housed in a building without heat and in the winter it isespecially desirable to increase the heat of the gas at one or both ofthe points indicated by the positions of the superheaters shown in Fig.1.

In the superheater shown in Figs. 6 and 7, a casing 30 has a heatinsulating material 31 therein With a cylinder 32 encased thereby. Saidcylinder has a disc 33 partitioning off the top of said cylinder, whilesaid disc has a plurality of openings 34 from each of which extends atube 35 down to a similar disc 36 closing the lower end of said cylinderand having corresponding openings 37.

A cover 38 connected to pipe 11 closes the lower end of said cylinderwhile a cover 39 connected to pipe 22 closes the upper end. A safetyvalve 40 is connected to the medial portion of said cylinder, while anoutlet pipe 41 having a control valve 42 is likewise connected to saidcylinder. A water gauge 43 extends from pipe 41 to pipe 44 having avalve 45 and is likewise connected to said cylinder. Electrical heatingcoils '46 connected to a source of electrical current surround the lowerends of said cylinder 32. A valve Water inlet pipe 47 also is connectedto said cylinder while an air outlet pipe 48 is positioned adjacent disc33 which outlet pipe is closed when all the air in said cylinder isexhausted.

In the operation of this superheater the hot refrigerant gas from pipe 6or 11 entering cover 38 passes through pipes 35 to cover 39 and throughpipe 22. Water is in troduced through pipe 47 to the desired height asindicated by the water gauge '43. The heating element 46 heats the waterin cylinder 32 turning the same to steam. The valve in pipe 48 remainsopen until the steam has driven all air from the interior of :thesuperheater and when that has been donethe valve is closed. The steamwithin the superheater then heats the tubes 35 and the gas passingthrough or contained therein. Safety valve 40 automatically releasessteam if the pressure rises above the pointat which said valve is set tooperate. Thus it will be understood, the temperature within cylinder 32can be controlled by controlling the current of heating elements 46.

Superheater 12' also may be interconnected to the hot gas line 6 forincreasing the temperature of the gas in that line since it is importantthat the ice be melted around the plugs 8 and adjacent end portion oftubes 3 before it is thawed from the remainder portions of the tubes 3.Either superheater 12 or superheater 12 or both can be employed,depending upon the conditions under which the machine is operating, andas experience may indicate is desirable. Also other types ofsuperheaters such as superheater 31 can be used in place of superheater12.

It is to be appreciated that the ice making machine disclosed herein aswell as the particular forms of superheaters are merely by way ofexample only. Superheaters can equally as well be included in othertypes of ice making machines for controlling the temperature of thedefrosting gas in view of the teachings disclosed herein. Likewiseconventional forms of superheaters can be employed for heating the gasto the temperature desired.

Accordingly, the present invention is capable of a variation and changesthereto as come within the scope of the appended claims are deemed to bea part of the present invention.

What I claim is:

1. In an ice making machine having at least one upright cylinder forproducing ice on the exterior thereof including a chamber connected tothe lower end of said cylinder, a pipe for conducting a heating fluid tosaid chamber for loosening ice formed around the lower end of saidcylinder and said chamber, a closed casing having said pipe connected atopposite ends thereof, a parti tion in said casing, a plurality of pipesextending through said partitions for the passage of fluid from saidfirst mentioned pipe, controlled means for supplying steam at desiredtemperatures between said partitions and exteriorly of said plurality ofpipes for superheating the fluid passing therethrough whereby fluid at acontrolled high temperature will reach said chamber for loosening icearound said chamber and the lower'end of said cylinder.

2. In an ice making machine as claimed in claim 1, a controlled pipeconnecting said cylinder and said chamber for feeding said fluid fromsaid chamber to said cylinder, and means for superheating said fluidpassing through said pipe whereby said fluid at a given temperature willbe fed into said cylinder for melting ice therearound sufficient tocause said ice to slide from said cylinder.

References Cited in the file of this patent UNITED STATES PATENTS170,508 Beath Nov. 30, 1875 2,384,714 Villiger Sept. 11, 1945 72,397,347 Gruner Mar. 26, 1946 2,563,686 Archibald Aug. 7, 19512,575,509 Bayston Nov. 20, 1951 2,618,129 Williams Nov. 18, 19522,641,908 La Porte June 16, 1953 2,674,858 Magnuson Apr. 13, 19542,749,721 Trepaud June 12, .1956

